Matches in SemOpenAlex for { <https://semopenalex.org/work/W4308341927> ?p ?o ?g. }
- W4308341927 endingPage "4574" @default.
- W4308341927 startingPage "4557" @default.
- W4308341927 abstract "We identify two ultra-cool ($T_mathrm{eff} < 4000$ K) metal-polluted (DZ) white dwarfs WDJ2147$-$4035 and WDJ1922$+$0233 as the coolest and second coolest DZ stars known to date with $T_mathrm{eff} approx 3050$ K and $T_mathrm{eff} approx 3340$ K, respectively. Strong atmospheric collision-induced absorption (CIA) causes the suppression of red optical and infra-red flux in WDJ1922$+$0233, resulting in an unusually blue colour given its low temperature. WDJ2147$-$4035 has moderate infra-red CIA yet has the reddest optical colours known for a DZ white dwarf. Microphysics improvements to the non-ideal effects and CIA opacities in our model atmosphere code yields reasonable solutions to observations of these ultra-cool stars. WDJ2147$-$4035 has a cooling age of over 10 Gyr which is the largest known for a DZ white dwarf, whereas WDJ1922$+$0233 is slightly younger with a cooling age of 9 Gyr. Galactic kinematics calculations from precise Gaia EDR3 astrometry reveal these ultra-cool DZ stars as likely members of the Galactic disc thus they could be pivotal objects in future studies constraining an upper age limit for the disc of the Milky Way. We present intermediate-resolution spectroscopy for both objects, which provides the first spectroscopic observations of WDJ2147$-$4035. Detections of sodium and potassium are made in both white dwarfs, in addition to calcium in WDJ1922$+$0233 and lithium in WDJ2147$-$4035. We identify the magnetic nature of WDJ2147$-$4035 from Zeeman splitting in the lithium line and also make a tentative detection of carbon, so we classify this star as DZQH. WDJ1922$+$0233 likely accreted planetary crust debris, while the debris composition that polluted WDJ2147$-$4035 remains unconstrained." @default.
- W4308341927 created "2022-11-11" @default.
- W4308341927 creator A5014472356 @default.
- W4308341927 creator A5019998564 @default.
- W4308341927 creator A5031123948 @default.
- W4308341927 creator A5049843538 @default.
- W4308341927 creator A5052751781 @default.
- W4308341927 creator A5060549482 @default.
- W4308341927 creator A5061472080 @default.
- W4308341927 creator A5061619584 @default.
- W4308341927 date "2022-11-05" @default.
- W4308341927 modified "2023-10-02" @default.
- W4308341927 title "Spectral analysis of ultra-cool white dwarfs polluted by planetary debris" @default.
- W4308341927 cites W147232447 @default.
- W4308341927 cites W1625632539 @default.
- W4308341927 cites W1839523728 @default.
- W4308341927 cites W1874246693 @default.
- W4308341927 cites W1966852370 @default.
- W4308341927 cites W1970928390 @default.
- W4308341927 cites W1972709162 @default.
- W4308341927 cites W1980456237 @default.
- W4308341927 cites W1983295796 @default.
- W4308341927 cites W1987260592 @default.
- W4308341927 cites W1992845500 @default.
- W4308341927 cites W1996197707 @default.
- W4308341927 cites W1997008272 @default.
- W4308341927 cites W1998520428 @default.
- W4308341927 cites W2001560461 @default.
- W4308341927 cites W2002752196 @default.
- W4308341927 cites W2006136210 @default.
- W4308341927 cites W2007601911 @default.
- W4308341927 cites W2009945539 @default.
- W4308341927 cites W2010188916 @default.
- W4308341927 cites W2011035608 @default.
- W4308341927 cites W2017133327 @default.
- W4308341927 cites W2018982227 @default.
- W4308341927 cites W2019574966 @default.
- W4308341927 cites W2027164640 @default.
- W4308341927 cites W2027788009 @default.
- W4308341927 cites W2028564308 @default.
- W4308341927 cites W2028678583 @default.
- W4308341927 cites W2034761906 @default.
- W4308341927 cites W2036212611 @default.
- W4308341927 cites W2038334622 @default.
- W4308341927 cites W2041459294 @default.
- W4308341927 cites W2044739223 @default.
- W4308341927 cites W2047994923 @default.
- W4308341927 cites W2052237972 @default.
- W4308341927 cites W2052937506 @default.
- W4308341927 cites W2055186625 @default.
- W4308341927 cites W2061169145 @default.
- W4308341927 cites W2061767396 @default.
- W4308341927 cites W2068058187 @default.
- W4308341927 cites W2075192668 @default.
- W4308341927 cites W2076362424 @default.
- W4308341927 cites W2078620156 @default.
- W4308341927 cites W2082211330 @default.
- W4308341927 cites W2084388331 @default.
- W4308341927 cites W2090232195 @default.
- W4308341927 cites W2092740243 @default.
- W4308341927 cites W2093211363 @default.
- W4308341927 cites W2096471541 @default.
- W4308341927 cites W2103024508 @default.
- W4308341927 cites W2104311895 @default.
- W4308341927 cites W2106365190 @default.
- W4308341927 cites W2120176236 @default.
- W4308341927 cites W2143051755 @default.
- W4308341927 cites W2148870695 @default.
- W4308341927 cites W2156895019 @default.
- W4308341927 cites W2157917411 @default.
- W4308341927 cites W2175046768 @default.
- W4308341927 cites W2227274187 @default.
- W4308341927 cites W2327648921 @default.
- W4308341927 cites W2422404559 @default.
- W4308341927 cites W2596926580 @default.
- W4308341927 cites W2764173864 @default.
- W4308341927 cites W2784495055 @default.
- W4308341927 cites W2853905819 @default.
- W4308341927 cites W2883698894 @default.
- W4308341927 cites W2894725121 @default.
- W4308341927 cites W2913305412 @default.
- W4308341927 cites W2922742761 @default.
- W4308341927 cites W2945098182 @default.
- W4308341927 cites W2955236351 @default.
- W4308341927 cites W2980833947 @default.
- W4308341927 cites W2983581670 @default.
- W4308341927 cites W2985988539 @default.
- W4308341927 cites W3008853589 @default.
- W4308341927 cites W3030469693 @default.
- W4308341927 cites W3030528044 @default.
- W4308341927 cites W3085521811 @default.
- W4308341927 cites W3094818009 @default.
- W4308341927 cites W3098122642 @default.
- W4308341927 cites W3098546722 @default.
- W4308341927 cites W3098951254 @default.
- W4308341927 cites W3099466126 @default.
- W4308341927 cites W3099520098 @default.
- W4308341927 cites W3099604106 @default.